Under Liccardo's proposal, which would require approval from the City Council, gun owners would have to either carry liability insurance or pay a fee to cover emergency response and medical care for victims of gun violence.

Liccardo likened the proposal to attempts to lower smoking rates and car crashes. Motorists, he pointed out, are required to carry auto insurance, and tobacco consumption is taxed both to discourage smoking and cover the costs of smoke-related illnesses and death.

Gun rights groups are vowing to take San Jose to court if the City Council approves the measures. "We think it's really misguided," said George Lee, an attorney representing firearm groups like the Firearms Policy Coalition.

Under Liccardo's plan, liability insurance would cover the accidental discharge of a gun, along with intentional acts by people who steal or borrow a gun from a gun owner. He acknowledged that insurers won't cover intentional conduct by a gun owner.

But Lee pushed back at the idea that any intentional criminal acts, regardless of who commits them, would be insurable. And, he said, a liability insurance program wouldn't stop someone like the Gilroy shooter — who on July 28 killed three people and wounded more than a dozen others before turning the gun on himself at the world-famous Gilroy Garlic Festival.

"It's yet another burden on gun owners," he said of the idea, suggesting the mayor was grasping for a way to feel better about the incident.

Liccardo acknowledged there "may need to be some evolution in the (insurance) industry," but he hopes other cities locally and elsewhere will consider the proposal in the future.

None of the proposals will become law immediately. The insurance program and fee would have to be approved by the City Council, and a tax would have to make its way to voters through the ballot.